Assessment of Offspring DNA Methylation across the Lifecourse Associated with Prenatal Maternal Smoking Using

Frank de Vocht1, Andrew J Simpkin2,3, Rebecca C Richmond4

  • 1School of Social and Community Medicine, University of Bristol, Bristol BS8 2PS, UK. frank.devocht@bristol.ac.uk.

Insights

Maternal smoking during pregnancy can affect child health through DNA methylation changes. A new Bayesian model reveals sustained effects on offspring DNA methylation, confirming links to genes like MYO1G and GFI1.

Area of Science:

  • Epigenetics
  • Developmental Biology
  • Environmental Health

Background:

  • Maternal smoking in pregnancy is linked to offspring ill-health.
  • DNA methylation is a potential mediator of these effects.
  • Analyzing genome-wide DNA methylation data presents challenges due to CpG site correlations.

Purpose of the Study:

  • To investigate the longitudinal effects of maternal smoking in pregnancy on offspring DNA methylation.
  • To apply a Bayesian hierarchical mixture model to analyze correlated DNA methylation data, avoiding data reduction methods.

Main Methods:

  • Utilized longitudinal DNA methylation data from a UK birth cohort (birth, age 7, 17).
  • Employed a Bayesian hierarchical mixture model to analyze genome-wide DNA methylation patterns.
  • Investigated associations between maternal smoking and offspring DNA methylation at CpG sites.

Main Results:

  • Replicated associations between maternal smoking and offspring DNA methylation at 4 previously identified smoking-related CpG sites.
  • Confirmed findings in well-known smoking-related genes MYO1G and GFI1.
  • Identified further weak associations at the AHRR and CYP1A1 loci.

Conclusions:

  • The Bayesian hierarchical mixture model is effective for analyzing longitudinal DNA methylation data.
  • This method offers an alternative to data reduction techniques in epigenome-wide association studies.
  • The findings reinforce the role of DNA methylation in mediating the long-term health impacts of maternal smoking.